Relationship of Ostial Pulmonary Vein Scar with Reduction in Pulmonary Vein Size after Radiofrequency Ablation for the Treatment of Atrial Fibrillation: An Observational Cohort Study

Citation : Thomas H. Hauser, MD, MMSc, MPH, Dana C. Peters PhD, John V. Wylie, MD, Catherine Lau, MD, Mark E. Josephson MD, Warren J. Manning, MD

Background: Radiofrequency (RF) ablation procedures to electrically isolate the pulmonary veins (PV) from the left atrium are frequently used to treat atrial fibrillation. We hypothesized that changes in PV size after RF ablation would correlate with the volume of ostial PV scar as assessed by high resolution late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR).
Methods: The study cohort included 23 consecutive subjects. Contrast enhanced PV CMR angiography and LGE were obtained before and 42 ± 18 days after RF ablation.
Results: Patients with 2 left (LPV) and 2 right PVs (RPV) (62.6%), 2 LPVs and 3 RPVs (17.3%) and 1 LPV and 2 RPVs (14.2%) made up the three most common variants. In the 2-LPV/2-RPV anatomy, the ostial size and area of the RPVs were larger than their corresponding LPVs (p<0.001), and the ostial size and area of the superior PVs were larger than their corresponding inferior PVs (p<0.001). In the 2-LPV/3-RPV anatomy, the total area of the RPVs was larger than the total area of the LPVs (p<0.001). In the 1-LPV/2-RPV anatomy, the ostial size of the left common PV was larger than either right PV (p<0.007). However, the total area of the RPVs was larger than the area of the left common PV (p<0.002). The left common PV was also larger than any of the left veins in any of the other anatomies. The total PV area between the three most common anatomies was not significantly different.
Conclusion: PV size decreases significantly after RF ablation for the treatment of AF. The change in PV size is linearly related to the quantity of LGE scar at the PV ostium.